There is no minimum GPA required for admission to Stanford. However, Stanford does provide data on applicants and incoming classes. That data show that a higher GPA increases the likelihood of admission.
In 2014, Stanford admitted 5.1 percent of freshman applicants. Of those who applied with a 4.0 GPA, 6 percent were admitted. Of those who applied a GPA below 3.7, only 2 percent were admitted. Applicants with a GPA between 3.7 and 4.0 were admitted at a rate of 4 percent.
Another important factor for admission is SAT or ACT scores. The percentage of students admitted in 2014 who had perfect SAT scores in any category was higher than the percentage of students admitted with a perfect 4.0 GPA.